taken from patagonia website...
Staying inside isn't the only way to stay dry – enjoy the trails in all conditions with fully seam-sealed waterproof/breathable protection. The Rain Shadow Jacket, now with an improved fit, is made from a packable and lightweight 2.5-layer tear-resistant nylon fabric with a waterproof/breathable H2No® barrier and Deluge® DWR (durable water repellent) finish. On the inside, a raised pattern diffuses and channels moisture away from the skin, aids in hassle-free layering, and enhances long-term durability. Features include a helmet-compatible, roll-down 2-way-adjustable hood; a storm flap with rain gutter over the center-front 2-way zipper and pit zips; water-resistant zippers on handwarmer pockets; partially elasticized self-fabric cuff tabs and a drawcord hem.
again, taken from patagonia site...
H2No® waterproof/breathable 2.5-layer tear-resistant fabric
Interior surface texture channels moisture away from skin, protects the waterproof barrier from abrasion and slides easily over layers
Roll-down, 2-way-adjustable hood
Center-front zipper with storm flap
Reverse-coil DWR-coated pit zips with storm flap Pockets: two handwarmers with PU coated zippers
Self-fabric cuff tabs
2.5-layer, 2.5-oz 100% nylon with a waterproof/breathable H2No barrier and Deluge® DWR (durable water repellent) finish
369 g (13 oz)
I use this jacket for everything from walking around town to the last layer of clothing for a long unplanned night exposed to the elements.
This jacket is simple and that is what I like about it. It has a loose fit that allows ample layering underneath yet isn't so big that it gets in the way. it is as breathable as any other rain shell I've worn and stands up to abuse fairly well for suck a thin shell. I've never had problems with rain or snow getting through.
If i had to have a complaint it would be that the hood is a little tight to wear with a helmet. it does work decently with a helmet but it could be a bit more comfortable.
On a side note, the sizing of these jackets is different than most companies. I usually wear a small in most other brands, but an XS in Patagonia seems to fit like most other smalls. If you're looking into getting this jacket, try it on or order a size smaller than you normally do.